Bi-wire/bi-amp

[PENG]

Out of curiosity I just took a peek at the Polk forum, and not surprisingly, the same misconception seems prevalent over there as well, with posts like what one very senior member said:

"...The full frequencies are traveling on both sets of cables, which are traveling from the same place to the same crossover, which splits the signal the same way it does with jumpers in place...."

"....Both sets of wires carry the exact same full range signal. Repeat that sentence until it sinks in....."

I browsed 5 pages of it, only one member challenged his statement and told him something like..." the signal voltage is the same but the current is not..." He got torn apart and ridiculed.. Okay I am exaggerating a little..

I am glad that after I pointed out the fact about the source voltage (same) vs current (different) thing, there has not been any repercussion so far, hopefully that is sustainable.

 

[Sparkus]

I know, I read a bunch of those and the answer to bi-amping these was really always the same.
So I tried the auto EQ setup a couple times this morning with the passive bi-amping...no change.
Then I went back to no bi-amp, using the same cable type as I use for all the speakers, as a jumper. Well, it sounded no different than the bi-amping. It's still better than it was before bi-amping...so I had something wrong or something else wasn't right...no idea what. Logically I would think terminations...no choice. The only thing I noticed is the binding posts are backing off as I very consciously tightened them when I bi-amped. I did so because I noticed they were not as tight as I thought I originally tightened them but I don't think they were so loose as to make a poor connection.

Anyway, so much for why it improved...leaving me with what was wrong in the first place?

 

[PENG]

I know, I read a bunch of those and the answer to bi-amping these was really always the same.
So I tried the auto EQ setup a couple times this morning with the passive bi-amping...no change.
Then I went back to no bi-amp, using the same cable type as I use for all the speakers, as a jumper. Well, it sounded no different than the bi-amping. It's still better than it was before bi-amping...so I had something wrong or something else wasn't right...no idea what. Logically I would think terminations...no choice. The only thing I noticed is the binding posts are backing off as I very consciously tightened them when I bi-amped. I did so because I noticed they were not as tight as I thought I originally tightened them but I don't think they were so loose as to make a poor connection.

Anyway, so much for why it improved...leaving me with what was wrong in the first place?

Were you using the copper strap kind of jumpers before. If it sounds the same as bi-amp now when using the same feed wires as jumpers then the original Polk Audio copper straps may be the problem, not tight, or just not very conductive for some reasons?

 

[Sparkus]

Were you using the copper strap kind of jumpers before. If it sounds the same as bi-amp now when using the same feed wires as jumpers then the original Polk Audio copper straps may be the problem, not tight, or just not very conductive for some reasons?

I checked that before I bi-amped. Polk puts a highly polished brass or brass plated copper jumper in. I hit the surface with a dremel and I think it's brass. Anyway, replaced that first, bi-amp was my last resort for all the reasons posted here and elsewhere. LOL. I'm gonna assume I left a strand hanging on both speakers or some damn thing...hell, eyes ain't what they used to be even with the bi-focals.
So, yeah, the only other thing is the post caps backing off, which I didn't notice bad sound until I started getting into Audacity and music file quality, about 7 months from purchase. So as I learned, I noticed more flaws...throw perception in the mix...maybe the posts did loosen enough and I went off thinking it was something else.

Good news is it sounds good now and I have some things to keep an eye on. Learned a lot here though...more than I'll grasp for awhile. Appreciated, very much. Again, you folks are top notch.
It's odd that HT sounded fine and 2 channel was the problem. I may never know for sure what really happened.

All that said, I think I could've chosen a better speaker for what I wanted. For now, they are working well enough. Highs are a bit high, mids are actually pronounced...for me pleasant and bass is there as I'd expect. Bear in mind my experience. It only lacks body right now...like the 3 ways are somewhat too individually defined...if that makes sense.

So, I'll pull the trigger on a sub...and start planning on new mains and center for X-mas, if I figure out what are best for primary 2 channel music and second HT. Don't be afraid to voice an opinion...it's always welcome.

 

[Sparkus]

Wanna field some questions on crossover?

 

[PENG]

First of all, if you don't mind I would like to do a recap here to save me time re-reading this whole thread and your other one where apparently you asked for input on the external amp scenario.

If I understood correctly as of now:

- You found out adding an external amp made no difference.
- You thought you were getting better SQ bi-amping but now you think it sounds the same either way, and you suspect the difference might have been due to some connections related issue, such as the binding posts backing off/coming loose?
- Speakers are RTiA7.
- AVR is the Onkyo TX-RZ820?

Please confirm the above and clarify the following:

1) Have you been comparing two channel music listening, or 5.1(i.e. you have a subwoofer) movies, or both?
2) Was the comparison done in direct, pure direct, or with AccEQ on?
3) How far do you sit from the speakers?
4) Approx. room dim?
5) Which external amp you have tried and found no difference to SQ?

Regardless, even with the incomplete info, I think you should bi-amp the RTiA7. I also believe the theoretical benefits of bi-amping in most cases won't be audible, but it won't hurt either so if you have the spare channels, you will get some real benefits such as:

1) In terms of head room: Polk Audio referred the two 7" drivers as subwoofers, so it is highly likely that with the metal jumpers removed, the two "subwoofers" will be one group and the tweeter and 6.5" mid the other. The average current peak split between the two groups would likely be roughly between 25/75 to 75/25 depending on the media contents. So passive bi-amping should give you a little more headroom for either group.

1) Bi-amp benefits (theoretical only): With the increased headroom, clipping will be less likely, so the theoretical advantage of passive bi-amp should be more likely realized whether you have the golden ears to hear the difference or not.

By the way, I took a quick look of available information for the TX-RZ820 and I am quite impressed with it's pedigree in terms of quality parts used such as:

- The preamp/vol control IC is still a LSI type, but it has virtually identical audio specs as Yamaha's integrated amp A-S801, both are Rohm's, much better than D&M's before they upgrade it to separate ICs in 2016/17.

- The block capacitors are 75 V rated, better than D&M and Yamaha's 71 V, negligibly but still..

- Very nice Z2 DAC, same as Yamaha's RX-A2060/3060(presumably),better than D&M's and Onkyo's own RZ1100.

So again, why leave 2 internal amps idled?

My questions 3) and 4) are quite relevant. For example, if you sit 10 ft, the RZ820 has enough output for a single RTiA7 to hit within 2 dB from reference level (105 dB peak) and that's just with a single channel (non biamp).

https://myhometheater.homestead.com/splcalculator.html

 

[Pogre]

When I was playing with my towers I did remove the jumpers to try out bi amping them. No difference whatsoever aside from the fact my speakers started to "pop" on power up with the extra wiring. Not a scary loud pop, but it was there and I wanted it gone so I put the jumpers back on and put them back the way they were.

I put some music on and now my right speaker sounded like crap. It was muffled, weak and wasn't even close to matching the speaker on the left. I contacted SVS and was told to loosen the terminals and wiggle the jumpers to make sure there was good contact between them and the binding posts then tighten them back up. That fixed it. Apparently it's a thing that happens sometimes and not a big deal. They told me folks had contacted them about it before and it was the first thing they had me try to troubleshoot. From what I've read I suspect you had the same thing going on.

You're still voicing dissatisfaction with 2 ch music and "lacking full body sound". A good subwoofer will fill that in, add full body, improve clarity and add weight over the full range. There's a big difference between a well designed and built subwoofer and what you have right now. I say this over and over on these forums, good bass is almost always underestimated to the uninitiated. It's not "just bass". Clean bass has to be heard to understand and once you do you'll never look back.

I was shocked when I first got some good subwoofers. I could not believe what I was hearing and all the advice I was given (advice I resisted) to upgrade my subs was validated. Of all the gear I've bought, after my speakers the subs were the biggest improvement in overall sound quality. Not just the low end. If you took the same money you spent on that amp and put it into a real sub you could have gotten something really nice and I think your eyes would be opened the same way mine were. We'd be having a completely different conversation right now.

I think you're pouring a lot of energy into things that will offer at best, tiny incremental improvements and in some cases none at all. You're learning some stuff along the way, but I think you're doing it the hard way. Someone here said something to the effect of trusting more in the objective side than the subjective side. That's good advice. The subjectivists will tend to push you toward expensive amps, woo-woo pseudo science, cables and power conditioners that make little to no difference and really only succeed in emptying your wallet, leaving you still dissatisfied with the sound as you listen with your $400 a foot Audioquest cables... The Polk forums are full of subjectivists.

I think you're giving up on your speakers too quickly and have yet to maximize and get the most out of your system. Get a good sub. Get everything set up, integrated and balanced, listen and tweak, then decide if it's time to rethink your main speakers. A good sub is something you'll want either way so it's not a waste and you might be surprised. You're trying almost everything else first and still haven't gotten where you want. I think you're closer than you realize. I love my speakers. I love them even more when my subs are playing with them.

I understand the resistance. I really do. My logic was, after all, "It's just bass and I have 2 subs already. I have plenty of bass. I don't need more.". I was in the same boat. I was wrong. It's not about "more bass", it's about good, clean bass. HD and Shady had to work me over pretty good before I finally gave in, but I did. I had to give up on my line of thinking and trust in the advice I was given. Major improvement! My whole system now has greatly improved sound quality from top to bottom. Just by upgrading my subs. I am so glad I listened now.

 

[Irvrobinson]

When I was playing with my towers I did remove the jumpers to try out bi amping them. No difference whatsoever aside from the fact my speakers started to "pop" on power up with the extra wiring. Not a scary loud pop, but it was there and I wanted it gone so I put the jumpers back on and put them back the way they were.

This indicates that your AVR has a poorly-designed bi-amping capability. Pops are normally the result of the amplifier channels not being muted before the pre-amp outputs powered down. Really well-designed pre-amps (and pre-amp stages in AVRs) mute their outputs first on power-down. Not so long ago I sent an Oppo Pre-amp/DAC back to the dealer because the outputs didn't mute on power-down, and my speakers popped. That was unacceptable.

 

[Pogre]

This indicates a that your AVR has a poorly-designed bi-amping capability. Pops are normally the result of the amplifier channels not being muted before the pre-amp outputs powered down. Really well-designed pre-amps (and pre-amp stages in AVRs) mute their outputs first on power-down. Not so long ago I sent an Oppo Pre-amp/DAC back to the dealer because the outputs didn't mute on power-down, and my speakers popped. That was unacceptable.

Well, I wasn't using my avr to power the speakers. I was using 2 channels for each speaker on my monolith to do the bi amping. Maybe it's the outputs in the pre stage of my avr, but I wasn't using its amp section.

 

[Irvrobinson]

Well, I wasn't using my avr to power the speakers. I was using 2 channels for each speaker on my monolith to do the bi amping. Maybe it's the outputs in the pre stage of my avr, but I wasn't using its amp section.

Were you using a single pair of pre-outs on the AVR and using splitters to feed the four amplifier channels?

 

[Pogre]

Were you using a single pair of pre-outs on the AVR and using splitters to feed the four amplifier channels?

Yup. That's exactly what I did.

 

[Irvrobinson]

Yup. That's exactly what I did.

If the external amp was being used in single amp mode, then the popping with bi-amping is a mystery (at least to me). Very curious.

 

[PENG]

If the external amp was being used in single amp mode, then the popping with bi-amping is a mystery (at least to me). Very curious.

He said he had a connection issue at the tower's terminals resulting in crap sound but fine after he wiggled the jumpers as instructed by SVS. So it is quite possible that the pops were also caused by the connection issue, just different severity/nature resulting in different symptoms, i.e., pops, or crap sound..

 

[Pogre]

Now I'm thinking about experimenting with bi amping again using 2 sets of preouts with my receiver in bi amp mode...

 

[Verdinut]

Now I'm thinking about experimenting with bi amping again using 2 sets of preouts with my receiver in bi amp mode...

That will be passive bi-amping and with the amp power that you have, you won't hear any improvement. Don't forget to remove the jumpers on the speaker cabinet terminals, or you will blow up your amps.

 

[Sparkus]

External amp; warmed the sound, did not help with volume or clarity. @Pogre said it
Bi-amping; definitely improved volume and SQ. After testing that, making changes to EQ in auto setup,
then returning to single channel, the volume and SQ were the same as bi-amp. Led me to
believe the problem was a physical one. Poor connection would be a logical cause.

Clarification:

1) 2 channel. I listen to music in 2 channel.
I usually use 1 to 3 songs (acoustic) to make comparisons. If an improvement is detected I run
thru some other songs from a different genre.
5.1 is movies. Did not notice the issues with 5.1 movies as I did with 2 channel music.
2) PureDirect I have gone back and forth with EQ simply to bring the highs down but it's On currently.

3) Distance 9' from the speaker face to my ear.

4) Dimension 14' x 15'

5) Ext Amp Parasound 2350. It made no difference to my ear in SQ at volume, it did give the music a
warmer sound, which I found pleasing...but not $800 worth of pleasure

Overall the difference is; I get audible volume, I can hear all instruments, at a lower volume
level and can play louder without distortion.

 

[Sparkus]

How do you listen to music? 2, 2.2 or 5.2?

 

[PENG]

How do you listen to music? 2, 2.2 or 5.2?

Who are you asking, everyone?

I listen to 2 and 2.1 using CDs, turntable, digital files, and 2, 2.1, 5.1, 7.1 using SACDs/DVDAs and BRs.
There is no such thing as 0.2, at least no such contents as of yet, though I have 5 subwoofers in the HT room.

 

[PENG]

Now I'm thinking about experimenting with bi amping again using 2 sets of preouts with my receiver in bi amp mode...

You have the Ultra towers right? Do you know if the mid range driver is grouped with the tweeter? I bet it is, but better get SVS to confirm that.

 

[PENG]

External amp; warmed the sound, did not help with volume or clarity. @Pogre said it
Bi-amping; definitely improved volume and SQ. After testing that, making changes to EQ in auto setup,
then returning to single channel, the volume and SQ were the same as bi-amp. Led me to
believe the problem was a physical one. Poor connection would be a logical cause.

Clarification:

1) 2 channel. I listen to music in 2 channel.
I usually use 1 to 3 songs (acoustic) to make comparisons. If an improvement is detected I run
thru some other songs from a different genre.
5.1 is movies. Did not notice the issues with 5.1 movies as I did with 2 channel music.
2) PureDirect I have gone back and forth with EQ simply to bring the highs down but it's On currently.

3) Distance 9' from the speaker face to my ear.

4) Dimension 14' x 15'

5) Ext Amp Parasound 2350. It made no difference to my ear in SQ at volume, it did give the music a
warmer sound, which I found pleasing...but not $800 worth of pleasure

Overall the difference is; I get audible volume, I can hear all instruments, at a lower volume
level and can play louder without distortion.

Thank you, okay then I would say definitely bi-amp them as there will be nothing to lose and some headroom to gain whether you need that or not. Also because you have the wires already.